<template>
  <div class="login-container">
    <el-form
      ref="loginForm"
      :model="loginForm"
      :rules="loginRules"
      class="login-form"
      auto-complete="on"
      label-position="left"
    >
      <div class="title-container">
        <h3 class="title">Login Form</h3>
      </div>

      <el-form-item prop="username">
        <span class="svg-container">
          <svg-icon icon-class="user" />
        </span>
        <el-input
          ref="username"
          v-model="loginForm.username"
          placeholder="Username"
          name="username"
          type="text"
          tabindex="1"
          auto-complete="on"
        />
      </el-form-item>

      <el-form-item prop="password">
        <span class="svg-container">
          <svg-icon icon-class="password" />
        </span>
        <el-input
          :key="passwordType"
          ref="password"
          v-model="loginForm.password"
          :type="passwordType"
          placeholder="Password"
          name="password"
          tabindex="2"
          auto-complete="on"
          @keyup.enter.native="handleLogin"
        />
        <span class="show-pwd" @click="showPwd">
          <svg-icon :icon-class="passwordType === 'password' ? 'eye' : 'eye-open'" />
        </span>
      </el-form-item>

      <el-button :loading="loading" type="primary" style="width:100%;margin-bottom:30px;" @click.native.prevent="handleLogin">Login</el-button>
    </el-form>
  </div>
</template>

<script>
import http from '@/utils/request'

export default {
  name: 'Login',
  data() {
    return {
      // 登录的form表单
      loginForm: {
        username: '关羽',
        password: '1'
      },
      loginRules: {
        username: [{ required: true, trigger: 'blur', message: '用户名不能为空' }],
        password: [{ required: true, trigger: 'blur', message: '密码不能为空' }]
      },
      loading: false,
      passwordType: 'password',
      redirect: undefined
    }
  },
  methods: {
    // 点击 "密码" 后面的眼睛的时候，显示密码的明文
    showPwd() {
      if (this.passwordType === 'password') {
        this.passwordType = ''
      } else {
        this.passwordType = 'password'
      }
      this.$nextTick(() => {
        this.$refs.password.focus()
      })
    },
    // 处理登录
    async handleLogin() {
      try {
        // 校验，如果校验失败，会抛出异常
        await this.$refs.loginForm.validate()
        // 代码能够下来，表示验证成功
        const r = await http.post('/login', this.loginForm)
        // 如果code码大于0，表示登录成功
        if (r.code > 0) {
          /**
           * 登录成功要做两件事:
           *  1.将jwt存储起来, 存到cookie中，存储的目的是后续要用。
           *  2.从jwt中提取用户名，在首页需要展示；
           */
          const access_token = r.access_token
          // this.$cookies这种使用方式只能在 vue组件中这么使用；非Vue组件是不能这么使用
          this.$cookies.set('access_token', access_token)
          // 获取jwt中间的payload，获取到的是一个Base64编码的字符
          const payload = access_token.split('.')[1]

          // 将base64的payload反编程为明文，但是得到的是一个字符串，
          // JSON.parse() 将一个JS的字符串对象转换成JS的对象 "{\"name\": \"刘备\"}" =>  {name: 刘备}
          let pl = decodeURIComponent(escape(window.atob(payload)))
          // console.log(pl)
          pl = JSON.parse(pl)
          // console.log(pl)
          const name = pl.sub // 获取到用户名
          // 将用户名存储到cookie中
          this.$cookies.set('username', name)

          this.$router.push('/dashboard')
        } else {
          // 表示用户名或者密码错误
          this.$message.error('用户名或者密码错误')
        }
      } catch (err) {
        console.log(err)
      }
    }
  }
}
</script>

<style lang="scss">
/* 修复input 背景不协调 和光标变色 */
/* Detail see https://github.com/PanJiaChen/vue-element-admin/pull/927 */

$bg:#283443;
$light_gray:#fff;
$cursor: #fff;

@supports (-webkit-mask: none) and (not (cater-color: $cursor)) {
  .login-container .el-input input {
    color: $cursor;
  }
}

/* reset element-ui css */
.login-container {
  .el-input {
    display: inline-block;
    height: 47px;
    width: 85%;

    input {
      background: transparent;
      border: 0px;
      -webkit-appearance: none;
      border-radius: 0px;
      padding: 12px 5px 12px 15px;
      color: $light_gray;
      height: 47px;
      caret-color: $cursor;

      &:-webkit-autofill {
        box-shadow: 0 0 0px 1000px $bg inset !important;
        -webkit-text-fill-color: $cursor !important;
      }
    }
  }

  .el-form-item {
    border: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.1);
    border-radius: 5px;
    color: #454545;
  }
}
</style>

<style lang="scss" scoped>
$bg:#2d3a4b;
$dark_gray:#889aa4;
$light_gray:#eee;

.login-container {
  min-height: 100%;
  width: 100%;
  background-color: $bg;
  overflow: hidden;

  .login-form {
    position: relative;
    width: 520px;
    max-width: 100%;
    padding: 160px 35px 0;
    margin: 0 auto;
    overflow: hidden;
  }

  .tips {
    font-size: 14px;
    color: #fff;
    margin-bottom: 10px;

    span {
      &:first-of-type {
        margin-right: 16px;
      }
    }
  }

  .svg-container {
    padding: 6px 5px 6px 15px;
    color: $dark_gray;
    vertical-align: middle;
    width: 30px;
    display: inline-block;
  }

  .title-container {
    position: relative;

    .title {
      font-size: 26px;
      color: $light_gray;
      margin: 0px auto 40px auto;
      text-align: center;
      font-weight: bold;
    }
  }

  .show-pwd {
    position: absolute;
    right: 10px;
    top: 7px;
    font-size: 16px;
    color: $dark_gray;
    cursor: pointer;
    user-select: none;
  }
}
</style>
